/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

namespace Lucene.Net.Spatial.Util
{
    /// <summary>
    /// Interface for Bitset-like structures.
    /// </summary>
    public interface IBits
    {
        bool Get(int index);
        int Length();
    }

    /// <summary>
    /// Empty implementation, basically just so we can provide EMPTY_ARRAY
    /// </summary>
    public abstract class Bits : IBits
    {
        public static readonly Bits[] EMPTY_ARRAY = new Bits[0];

        public virtual bool Get(int index)
        {
            throw new System.NotImplementedException();
        }

        public virtual int Length()
        {
            throw new System.NotImplementedException();
        }
    }

    /// <summary>
    /// Bits impl of the specified length with all bits set.
    /// </summary>
    public class MatchAllBits : Bits
    {
        private readonly int len;

        public MatchAllBits(int len)
        {
            this.len = len;
        }

        public override bool Get(int index)
        {
            return true;
        }

        public override int Length()
        {
            return len;
        }
    }

    /// <summary>
    /// Bits impl of the specified length with no bits set. 
    /// </summary>
    public class MatchNoBits : Bits
    {
        private readonly int len;

        public MatchNoBits(int len)
        {
            this.len = len;
        }

        public override bool Get(int index)
        {
            return false;
        }

        public override int Length()
        {
            return len;
        }
    }
}